Declarative Amsterdam

An executable conceptual model for biodiversity in planning law

Chris WallaceBristol Tree Forum and UWE Bristol

In the upcoming Environment Act due in parliament later this year, a methodology for assessing the biodiversity of a site and its improvement will be enshrined in UK planning law. The detailed calculations are embedded in an Excel spreadsheet of some complexity. Although spreadsheets (excluding macros) are arguably declarative, they presents some problems for the ease of comprehension of the calculations, traceability to supporting documents and validation.

This presentation will outline the problem, look at an alternative declarative implementation using an executable conceptual model written in XML with XQuery formula interpreted by an XQuery application running on eXist-db and consider some of the issues of software-defined legislation.

Further details on the current state of the project.

Presentation, 3 November 2023

Chris Wallace retired from lecturing on computing and information systems at the University of the West of England, Bristol some years ago. This has allowed more time for sailing, for making and for work on a variety of web-based projects. The web projects nearly all use XQuery with eXist-db supplemented with JavaScript. Chris has been an XQuery user for many years, initially on the development of a comprehensive faculty information system with his students which sadly did not survive his retirement. With Dan McCreary, Chris started the XQuery wikibook project in 2010 (which needs some love).  The largest of his current projects is a register of trees and green spaces in Bristol, developed under the auspices of the Bristol Tree Forum, a group of volunteers advocating for urban trees.  Other projects focus on local history and 3D printing, currently in ceramics.